Down-like fiber

ABSTRACT

The invention provides a down-like fiber which comprises a hollow stem and a plurality of shaped lobes arranged radially around the stem wherein each shaped lobe has a bottom end and a head end opposite the bottom end. The bottom end attaches to the surface of the hollow stem and two adjacent head ends do not connect to one another to form an opening. The present invention also provides a spinneret and a method for manufacturing the above fiber.

FIELD OF THE INVENTION

The present invention relates to a down-like fiber, particularly, to adown-like fiber with a hollow stem and a plurality of shaped lobes.

BACKGROUND OF THE INVENTION

Natural feathers consist of vaned feathers and down feathers; the formerhas hollow stems, and the latter does not. The arrangement of both vanedfeathers and down feathers forms irregular spaces, thereby trapping airto reduce heat dissipation and thus can provide warm effect. However,the warm effect of natural feathers is extremely decreased due toabsorption of water.

In the prior art, fibers with different shaped lobes such ascross-shaped, Y-shaped and W-shaped lobes have been disclosed. Forexample, U.S. Pat. No. 5,057,368 discloses a fiber comprising 3 or 4T-shaped lobes. Although the above fibers have capability of absorbingmoisture and relieving sweat, the warm effect thereof is not goodenough. Contrarily, polyester fibers sold in the market have a hollowstructure and thus possess the warm effect, but the effects of absorbingmoisture, relieving sweat and a soft touch feeling are poor.

Therefore, it is highly desired to have a fiber that not only has goodeffect of keeping warm but also possesses excellent effects of drainageand fast-drying, and a lightened weight and a soft tough feeling can beachieved as well.

SUMMARY OF THE INVENTION

To solve the above problems, the present invention provides a down-likefiber which possesses an effect of keeping warm just like feathers, andpresents an outstanding fast drying effect as well.

The present invention provides a down-like fiber which comprises ahollow stem and a plurality of shaped lobes arranged radially from thehollow stem as a center, wherein each of the shaped lobes comprises abottom end and a head end opposite the bottom end. The bottom endconnects to a surface of the hollow stem, and the head ends of twoadjacent shaped lobes do not connect with one another to form anopening.

According to one aspect of the present invention, the shaped lobes canbe T-shaped, cross-shaped, Y-shaped, ↑-shaped, ♀-shaped, W-shaped,H-shaped, V-shaped or rectangular-shaped and the number of the shapedlobes can range from 2 to 6.

According to one aspect of the present invention, the down-like fiberstated above can be a filament or a staple.

The present invention also provides a spinneret for manufacturing thedown-like fiber stated above. The spinneret comprises a plurality ofslits of spinning nozzles. Each of the slits of spinning nozzlescomprises an inner ring portion and an outer lobe portion which has abottom end and a head end opposite the bottom end wherein the bottom endconnects to the inner ring portion. The inner ring portions of theplurality of slits of spinning nozzles are arranged in a circle at aregular interval, and the head ends of two adjacent outer lobe portionsdo not connect with one another to form an opening.

According to one aspect of the present invention, the outer lobe portioncan be T-shaped, cross-shaped, Y-shaped, ↑-shaped, ♀-shaped, W-shaped,H-shaped, V-shaped or rectangular-shaped. The number of the slits ofspinning nozzles can range from 2 to 6.

The present invention also provides a method for manufacturing the abovedown-like fiber, which comprises extruding a polyester polymer inmelting form through the spinneret stated above.

The down-like fiber provided by the present invention has a hollow stemand shaped lobes which imitates the structure of feathers, and thus cannot only conserve heat dissipated from body but also lighten the weightof fiber, thereby providing a soft touch feeling. Moreover, since thehead ends of adjacent shaped lobes do not connect with each other, theditches formed therefrom can improve drainage functions. Accordingly,the effects of keeping warm and fast-drying can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawings will be provided by the Office upon request and paymentof the necessary fee.

FIG. 1 schematically shows the cross section of the down-like fiberhaving T-shaped lobes according to one embodiment of the presentinvention;

FIGS. 2A to 2H schematically show the cross sections of the down-likefibers having different shaped lobes according to embodiments of thepresent invention;

FIG. 3 shows a photograph of the cross section of physical samples ofdown-like fibers having T-shaped lobes;

FIG. 4 schematically shows the arrangement of several down-like fibershaving T-shaped lobes according to one embodiment of the presentinvention;

FIG. 5A schematically shows a spinneret used for manufacturing down-likefibers having T-shaped lobes according to one embodiment of the presentinvention;

FIG. 5B schematically shows a spinneret used for manufacturing down-likefibers having cross-shaped lobes according to one embodiment of thepresent invention; and

FIG. 6 shows a bar graph of warm effect tests.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 schematically shows the cross section of the down-like fiberhaving T-shaped lobes according to one embodiment of the presentinvention. In FIG. 1, the fiber 10 comprises a hollow stem 13 and fourT-shaped lobes 11 which arrange radially from the hollow stem 13 as acenter. Each of T-shaped lobes 11 comprises a head end 112 and a bottomend 111 wherein the bottom end 111 connects to the surface of the hollowstem 13, and the head ends 112 of two adjacent T-shaped lobes 11 do notconnect with one another to form an opening 12. The opening 12 can beused as a ditch to drain moisture.

FIGS. 2A to 2H schematically show the cross sections of the down-likefibers having different shaped lobes according to other embodiments ofthe present invention. As shown in FIGS. 2A to 2H, the shaped lobes canbe cross-shaped, Y-shaped, ̂-shaped, ♀-shaped, W-shaped, H-shaped,V-shaped or rectangular-shaped. The number of the shaped lobes ispreferably from 2 to 6. That is because if the number of the shapedlobes is above 6, the design of spinning nozzles will become morecomplicate and thus lead to increasing the cost; however, if the numberof the shaped lobes is too few, the drainage function and warm effect offibers will be affected.

FIG. 3 shows a photograph of the cross section of physical samples ofdown-like fibers having T-shaped lobes. According to FIG. 3, due to thedesign of T-shaped lobes, those fibers can keep certain spaces toprevent from being tightly packed. FIG. 4 schematically shows thearrangement of several down-like fibers having T-shaped lobes accordingto one embodiment of the present invention. In FIG. 4, since the headends 112 of the adjacent T-shaped lobes 11 do not connect to each other,the opening 12 formed therefrom can be used as a ditch. Since water canbe drained through the openings 12, the fabrics woven by the fiber 10demonstrate an outstanding drying effect after absorbing moisture orsweat. Also, many air rooms formed by the arrangement of the head ends112 of the T-shaped lobes 11, in combination with the closed hollowstems 13, can further conserve heat emitted from a human body, therebyenhancing the warm effect.

FIG. 5A schematically shows a spinneret for manufacturing a down-likefiber having T-shaped lobes according to one embodiment of the presentinvention. As shown in FIG. 5A, a spinneret 20 comprises four “

” shaped slits of spinning nozzles 21. Each of slits of spinning nozzles21 comprises an inner ring portion 211 and an outer lobe portion 213,wherein the outer lobe portion 213 has a bottom end 215 and a head end217 opposite the bottom end 215, and the bottom end 215 connects to theinner ring portion 211. The inner ring portions 211 of the four slits ofspinning nozzles 21 are arranged in a circle at a regular interval, andthe head ends 217 of two adjacent outer lobe portions 213 do not connectwith one another to form an opening 22. A polymer is extruded from theslits of spinning nozzles 21 which will further swell and connect at theinner ring portions 211 to form a hollow ring, thereby producing thefiber 10 shown in FIG. 1.

Polymers suitable for manufacturing fibers of the present inventioninclude but not limited to polyester, nylon, polyolefin,polyacrylonitrile or cellulose, wherein polyester can be polyethyleneterephthalate (PET), polybutylene terephthalate (PBT) or polypropyleneterephthalate (PPT); nylon can be nylon 6 (N6) or nylon 66 (N66); andpolyolefin can be polypropylene (PP) or polyethylene (PE). Besides,additives can be further added in the fibers of the present inventionwhich include but not limited to antibacterial and antifungal agents,anti-conductive agents, deodorants, anti-ultraviolet agents orfar-infrared agent.

FIG. 5B schematically shows a spinneret used for manufacturing down-likefibers of FIG. 2A which have cross-shaped lobes according to oneembodiment of the present invention. As shown in FIG. 5B, the spinneret30 comprises four “

” shaped slits of spinning nozzles 31. The outer lobe portion 313 of theslit of spinning nozzle 31 is “cross-shaped”. In other embodiments ofthe present invention, the outer lobe portion 313 can be Y-shaped,↑-shaped, ♀-shaped, W-shaped, H-shaped, V-shaped or rectangular-shapedto manufacture down-like fibers having different shaped lobes shown inFIGS. 2B to 2H.

The following further describes manufacturing examples of down-likefibers of the present invention and tests of effects.

EXAMPLE 1 Manufacture of Down-Like Staples Having T-Shaped Lobes

The polyester polymer in melting form is extruded through a spinneret asshown in FIG. 5A at spinning temperature of 290° C.; quenched by coolingair at a rate of 1.0 m/s; and spun at a spinning rate of 700 m/min. Thefilaments are drawn at a total elongation of 2.89 times followed bythermosetting at 160° C., cooling, wrinkling, oiling, drying, cutting,and packaging steps. The down-like staples of 3d*51 mm whose crosssection is a hollow stem with four T-shaped lobes are thus obtained.

EXAMPLE 2 Manufacture of Down-Like Staples Having Cross-Shaped Lobes

The polyester polymer in melting form is extruded through a spinneret asshown in FIG. 5B at spinning temperature of 290° C.; quenched by coolingair at a rate of 1.0 m/s; and spun at a spinning rate of 700 m/min. Thefilaments are drawn at a total elongation of 2.89 times followed bybeing thermosetting at 160° C. , cooling, wrinkling, oiling, drying,cutting, and packaging steps. The down-like staples of 3d*51 mm whosecross section is a hollow stem with four cross-shaped lobes are thusobtained.

EXAMPLE 3 Manufacture of Down-Like Filament Textured Yarn HavingT-Shaped Lobes

The polyester polymer in melting form is extruded through a spinneret asshown in FIG. 5A at spinning temperature of 290° C.; quenched by coolingair at a rate of 0.6 m/s; and winded at a spinning rate of 2500 m/min toproduce 120/36 partially oriented yarns (POY). The yarns are drawn at atotal elongation of 1.6 times followed by thermosetting at 160° C. andwinding steps. The 75/36 down-like filament textured yarns whose crosssection is a hollow stem with four T-shaped lobes are thus obtained.

EXAMPLE 4 Manufacture of Down-Like Filament Oriented Yarn HavingT-Shaped Lobes

The polyester polymer in melting form is extruded through a spinneret asshown in FIG. 5A at spinning temperature of 290° C.; quenched by coolingair at a rate of 0.6 m/s; and spun at a spinning rate of 4000 m/min. Theyarns are drawn at a total elongation of 2.0 times at the drawntemperature of 90° C. followed by thermosetting at 130° C. and windingsteps. The 75/36 down-like filament oriented yarns whose cross sectionis a hollow stem with four T-shaped lobes are thus obtained.

Test 1: Evaporation Rate Test

The evaporation rate tests of fabrics woven by the down-like fibershaving T-shaped lobes of the present invention, conventional hollowround polyester fibers, solid round polyester fibers and solid fibershaving other shaped lobes are described below.

First, a sample of size 10×10 cm is placed in an environment of constanttemperature and humidity (23° C., 65% RH) for 24 hours and then movedonto a scale. A given amount of water (W1, unit: gram) is dripped from 1centimeter above the fabric by using a volumetric pipet. After 5minutes, the remaining amount of water (W2, unit: gram) in the fabric isrecorded and the evaporation rate is calculated based on the followingformula:

Evaporation Rate=(W1−W2)/W1×100%

The test results are shown in Table 1. Sample 1 to 5 are double knitbird eye fabrics with a width of 36 inches*26 needles, which arerespectively woven by staples having T-shaped lobes of the presentinvention, solid staples having 4T cross section, solid staples havingcross cross section, solid round polyester fibers and hollow roundpolyester fibers (the above products are obtained from ShinkongSynthetic Fibers Corporation, in which the solid staples having 4T crosssection have been issued Taiwan Patent no. 1374952).

TABLE 1 sample 1 (the present 5 invention) 2 3 4 (comparative down-like(comparative (comparative (comparative example) staples example)example) example) hollow having solid staples solid staples solid roundround T-shaped having 4T having cross polyester polyester lobes crosssection cross section fiber fiber evaporation 76.8 73.5 69.2 50.1 49.6rate (%)

According to Table 1, the evaporation rate of the down-like fiber havingT-shaped lobes provided by the present invention is around 76.8%, whichis much better than 50.1% achieved by the solid round polyester fiberand 49.6% achieved by the hollow round polyester fiber. The test resultdemonstrates that since fibers of the present invention possess lobestructures as ditches, the fabric woven by fibers of the presentinvention can keep larger spaces between fibers, and thus facilitatedrainage. The fibers of the present invention exhibit a fast dryingeffect compared with conventional hollow or solid round polyesterfibers. Furthermore, the evaporation rate of fibers of the presentinvention is also higher than solid fibers having other cross sections(i.e. samples 2 and 3). This shows that compared with conventional solidfibers having 4T cross section or cross cross section, fibers of thepresent invention possess excellent drainage effect, and thus fabricswoven thereby can achieve fast drying effect without a muggy feeling.

Test 2: Warm-Keeping Test

The warm-keeping test of fabrics woven by down-like fibers havingT-shaped lobes of the present invention is described below. The test isperformed by AGEMA Thermal vision 900 thermal conductivity meter. A 500Whalogen lamp is used as a heat source to irradiate a sample for 10minutes at a distance of 100 centimeters. The temperature of the sampleis measured before and after exposure to the light. Samples 1 to 4represent double knit bird eye fabrics with a width of 36 inches*26needles which are respectively woven by four different fibers, includingdown-like fibers having T-shaped lobes of the present invention,conventional solid fibers having 4T cross section, solid round polyesterfibers and hollow round polyester fibers

TABLE 2 Before After Irradiation Irradiation Differences of Sample (°C.) (° C.) Temperatures 1 down-like fiber having 23.1 29.5 +6.4 T-shapedlobes (the present invention) 2 solid fibers having 4T 23.2 27.8 +4.6cross section (comparative example) 3 solid round polyester 23.1 25.6+2.5 fiber (comparative example) 4 hollow round 23.2 26.3 +3.1 polyesterfiber (comparative example)

FIG. 6 shows a bar graph based on the results of warm-keeping test.According to Table 2 and FIG. 6, the temperature of the fabric woven byfibers of the present invention is obviously raised after irradiationwith a light source. The increase of temperature is much greater thanthose of round polyester fibers (i.e. sample 3 and sample 4), and abetter warm effect is also presented compared with conventional solidfibers having 4T cross section (i.e. sample 2).

According to the above, the hollow stem of the down-like fiber providedby the present invention, which is like a feather stem, not only reducesthe weight of fiber but also provides effect of keeping warm. Moreover,the shaped lobes around the main stem provide several air rooms due todisconnection of adjacent head ends. The ditch structures formedtherefrom can further enhance the effects of heat conservation, andimprove the effects of drainage and fast-drying. Accordingly, thedown-like fibers provided by the present invention can overcomedisadvantages of bird feathers, i.e. decrease in the effect of keepingwarm as a result of moisture absorption, and of conventional fibershaving shaped lobes which has a drainage function but a poor effect ofkeeping warm. Meanwhile, since the weight of fiber of the presentinvention has been reduced, a down-like touch feeling is reserved.

Exemplary embodiments have been described herein, but do not intend tolimit the scope of the present invention. It will be understood by thoseskilled in the art that various changes and modifications may be madetherein without departing from the spirit and the scope encompassed bythe appended claims. Therefore, the scope of the present invention isdetermined by the claims that follow.

What is claimed is:
 1. A down-like fiber, comprising: a hollow stem; anda plurality of shaped lobes, arranged radially from the hollow stem as acenter, wherein each of the shaped lobes comprises a bottom end and ahead end opposite the bottom end, and the bottom end connects to asurface of the hollow stem, and the head ends of two adjacent shapedlobes do not connect with one another to form an opening.
 2. The fiberof claim 1, wherein the shaped lobes are T-shaped, cross-shaped,Y-shaped, ↑-shaped, ♀-shaped, W-shaped, H-shaped, V-shaped orrectangular-shaped.
 3. The fiber of claim 1, wherein the number of theshaped lobes is from 2 to
 6. 4. The fiber of claim 1, wherein the fiberis a filament or a staple.
 5. A spinneret for use in manufacturing thedown-like fiber of claim 1, comprising a plurality of slits of spinningnozzles, each of the slits of spinning nozzles comprising: an inner ringportion; and an outer lobe portion, comprising a bottom end and a headend opposite the bottom end, wherein the bottom end connects to theinner ring portion; wherein the inner ring portions of the plurality ofslits of spinning nozzles are arranged in a circle at a regularinterval, and the head ends of two adjacent outer lobe portions do notconnect with one another to form an opening.
 6. The spinneret of claim5, wherein the outer lobe portion are T-shaped, cross-shaped, Y-shaped,↑-shaped, ♀-shaped, W-shaped, H-shaped, V-shaped or rectangular-shaped.7. The spinneret of claim 5, wherein the number of the slit of spinningnozzle is from 2 to
 6. 8. A method for manufacturing the down-like fiberas claimed in claim 1, comprising extruding a polyester polymer inmelting form through a spinneret, wherein the spinneret comprises aplurality of slits of spinning nozzles, and each of the slits ofspinning nozzles comprises: an inner ring portion; and an outer lobeportion, comprising a bottom end and a head end opposite the bottom end,wherein the bottom end connects to the inner ring portion; wherein theinner ring portions of the plurality of slits of spinning nozzles arearranged in a circle at a regular interval, and the head ends of twoadjacent outer lobe portions do not connect with one another to form anopening.